U.S. Pat. No. 3,518,818 discloses a pickling cucumber harvester comprising a pick-up device which is configured with two lateral wheel disks. The peripheral region of these disks bites into the ground and serves to clear a harvesting path, with a circulating conveyor, tailored to the path width and having tines for raising and conveying the cucumber plants to the harvesting machine, and with a cutting device, extending over the path width, for cutting off the cucumber plants close to the ground directly after the raising, the cutting device being controlled in height by means of a ground sensing device. The envisaged cut-off of the cucumber plants above the ground surface permits use even in non-sandy soils, in which the commonly known cut-off a few centimeters beneath the ground surface (e.g. U.S. Pat. No. 3,603,067) would lead to a transportation of earth into the harvesting machine and hence to considerable disturbances.
Disturbances in the harvesting operation may also be caused by a pile-up of plants in front of the harvesting machine. For yield reasons, moreover, it is necessary to largely prevent the cucumber fruits from being damaged by the harvesting operation. In both respects, the known pick-up device fails to meet the requirements.
A shortcoming of known pick-up devices is their use of a circulating conveyor which is a chain conveyor equipped with rigid metal tines, and that within the conveying track of the circulating conveyor the cucumber plants are lifted continually off the tines, whereupon the cucumber plants, following full retraction of the tines, are no longer forcibly advanced and are not guided. This frequently results in a pile-up of plants in front of the harvesting machine, which causes interruptions to the harvesting operation. Furthermore, it has hitherto not been possible to use a known pick-up device for harvesting purposes in plasticulture. Due to unevenness of the ground and the lack of an appropriate height control for the cutting device and the circulating conveying tines, the plastic sheeting ends up being seized and torn to shreds. In plasticulture, which is particularly sensible in climatically less favored regions from the yield aspect, the cucumber harvest has until now, therefore, had to be carried out expensively by hand.
The object of the invention is hence to provide a pick-up device which is suitable for use with plasticulture, largely prevents interruptions caused by operating disturbances and ensures a gentle treatment of the cucumber plants.